Yes, it is correct to say you are "finding pathology" after EBUS-FNA
After EBUS with fine needle aspiration, you are obtaining tissue samples that will be analyzed by pathology to establish a diagnosis—so yes, you are "finding pathology" in the sense that you are discovering what the pathological diagnosis is. However, it's important to understand the workflow and terminology precisely.
Understanding the EBUS-FNA Diagnostic Process
The procedure itself involves:
- Real-time ultrasound-guided sampling of mediastinal/hilar lymph nodes or masses 1
- Tissue acquisition through fine needle aspiration that yields cytologic material
- Pathological analysis that follows to establish the diagnosis
What "Finding Pathology" Actually Means
When you perform EBUS-FNA, you are:
- Obtaining specimens that will undergo cytopathological evaluation 2
- Discovering the diagnosis through microscopic examination of the aspirated material
- Confirming tissue diagnosis rather than relying solely on imaging features 1
The guidelines explicitly state that "ultrasonographic features can be used to predict malignant and benign diagnoses, but tissue samples should still be obtained to confirm a diagnosis" 1. This underscores that EBUS-FNA is the method by which you definitively establish what pathology is present.
Diagnostic Performance
EBUS-FNA has demonstrated:
- Median sensitivity of 89% for mediastinal staging in lung cancer 1
- Specificity approaching 100% in multiple studies 3, 4
- Overall diagnostic yield of 71%, with better performance for mediastinal (N2) lymph nodes (72%) compared to hilar (N1) nodes (64%) 4
Important Caveats About the Pathology Results
Adequacy Issues
- Approximately 11-18% of samples may be inadequate or less than optimal 4
- Suboptimal samples carry a 21% risk of malignancy on follow-up, including cases with fibrosis or hyalinization 4
- The negative predictive value ranges from 88-93%, meaning negative results don't completely rule out malignancy 5
Diagnostic Limitations
- Cytological subtyping has limitations compared to histology 3
- Approximately 11.8% diagnostic discordance can occur between rapid on-site evaluation and final pathology, mostly related to tumor subtyping challenges 3
- False-negative results occur in 3-23% of cases depending on sample adequacy 4
Recommendations for Additional Sampling
For suspected or known non-small cell lung cancer, obtain additional samples beyond those needed for diagnosis to enable molecular analysis (Grade 1C) 1. This is critical for treatment planning and should be done at the time of initial sampling.
Number of Passes
In the absence of rapid on-site evaluation, perform a minimum of 3 separate needle passes per sampling site 1. More passes are associated with better adequacy rates 3.
Clinical Bottom Line
You are indeed "finding pathology" through EBUS-FNA—the procedure allows you to obtain tissue that reveals the pathological diagnosis. However, recognize that negative or inadequate results require clinical correlation and may necessitate repeat sampling or alternative diagnostic approaches, as the negative predictive value is not 100% 4, 5.